Comment #7 on issue 3560 by [email protected]: solve() is a giant mess
http://code.google.com/p/sympy/issues/detail?id=3560
"So I think a Solution class could solve all these problems."
It would be nice to have solve(x+1<0,x) simply return Interval(-oo, -1) for
example.
IMO, there should be a generic Set class from which inherits things as
different as solutions of solve(x+1<0,x) or solve(sin(x), x). A class which
represent a mathematical set.
And probably a Solutions class for equations for which we can't find all
solutions (something like RootOf).
I think something like sets of named tuples may be considered as well, when
there are many variables.
This enables access by name (`sol.x for sol in solutions`), but mimics
better mathematical structure.
(I don't know if it has already been discussed.)
"I'm not sure what you would expect from solve(x**2 + y**2 < 1, (x, y))"
Neither I am. Maybe a Disk class (this is not such an exotic object when
working with complexes).
Yet, for now, I admit it is mostly theory, but I expect such problems to
appear in the future if solve() output differs too much from mathematical
sets.
"
By the way, the practical reason for returning dicts is that solve guesses
the variables from the equations, so that you can just type solve([x - y, x
+ y]) (instead of solve([x - y, x + y], (x, y)))."
Guessing is just syntactic sugar, so for me alphabetical order is enough.
If you need more, sets of named tuples may do the trick, and preserve the
{(x1,y1), (x2,y2)... } mathematical structure.
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